基于断裂力学疲劳裂纹扩展研究及修复试验

Study of Fatigue Crack Extension Based on Fracture Mechanics and Repair Tests

摘要:

针对正交异性钢桥面板部分疲劳部位裂纹扩展行为进行分析时，基于有限元模型，引入初始裂纹，得到裂纹尖端应力强度因子与循环荷载下不同疲劳细节的裂纹扩展过程，与实桥裂纹情况对比后发现两者基本一致。在此基础上，采用止裂孔法、CFRP布粘贴加固+止裂孔法加固修复了带有裂纹的横隔板弧形开口试件，并对修复后的试件分别进行静力和疲劳试验，所得试验结果也与有限元计算结果基本一致。针对正交异性钢桥面裂纹的修补与维护进行研究具有重要意义，可供相似工程参考。

Abstract:

Aiming at the analysis of the crack extension behaviour of fatigue parts of orthotropic steel bridge decks, based on the finite element model, the initial crack is introduced, and the crack extension process of different fatigue details under the stress intensity factors of the crack tip and the cyclic load is obtained. After compared with the actual bridge crack situation, it is found that the two are basically the same. On this basis, the arc-shaped opening specimens of the transverse partition with cracks are repaired by using the anti-crack hole method, and the CFRP cloth bonding reinforcement + anti-crack hole method reinforcement. And the static and fatigue tests are respectively conducted on the repaired specimens. The obtained test results are also basically consistent with the finite element calculation results. It is of great significance to conduct research on the repair and maintenance of cracks in orthotropic steel bridge decks, which can serve as a reference for similar projects.